Deligne–Simpson conjecture for Coxeter connections

About 5 years old · traced to

Let GG be a simple complex group with Lie algebra g⁡\operatorname{\mathfrak{g}}. Fix a Coxeter GG-formal type A\mathscr{A} of slope r/hr/h with gcd⁡(r,h)=1\gcd(r,h)=1. A nilpotent orbit threshold is a nilpotent orbit Or⊂g⁡\mathscr{O}^r\subset\operatorname{\mathfrak{g}} such that the Deligne–Simpson problem is governed by the closure order ⪰\succeq. Deligne–Simpson conjecture for Coxeter connections. There exists a nilpotent orbit Or⊂g⁡\mathscr{O}^r\subset\operatorname{\mathfrak{g}} such that the Deligne–Simpson problem for Coxeter GG-connections with initial data A\mathscr{A} and nilpotent orbit O\mathscr{O} has a positive solution if and only if O⪰Or\mathscr{O}\succeq\mathscr{O}^r. Moreover, if r>hr>h, then Or=0\mathscr{O}^r=0, so the Deligne–Simpson problem always has a positive solution. This extends the preceding solution for GL⁡n\operatorname{GL}_n-connections to simple complex groups; the candidate is stated in the source as a conjectural generalization, while the supplied parser gives no resolution evidence.

References

Primary source

Maitreyee C. Kulkarni, Neal Livesay, Jacob P. Matherne, Bach Nguyen and Daniel S. Sage, “The Deligne-Simpson problem for connections on G_m with a maximally ramified singularity”, arXiv:2108.11029 (2022).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.